Abstract
Thyroid diseases and obesity are major health issues in the 21st century. While fatty acids (FAs) are known to influence various conditions, their role in thyroid disorders remains unclear. This study investigated FA profiles in patients with thyroid diseases to assess their diagnostic potential. From 891 patients treated at the Thyroid Cancer Center of the Medical University of Gdansk (2021-2024), 173 were selected for FA analysis using gas chromatography-mass spectrometry. Receiver operating characteristic (ROC) analysis evaluated the predictive value of individual FAs, and metabolite set enrichment analysis (MSEA) identified changes in FA metabolism. Results showed significant alterations in FA profiles among thyroid disease patients. Notably, levels of specific n-3 polyunsaturated FAs (ALA, EPA, DHA) were reduced in Hashimoto's thyroiditis (HT) compared to healthy controls, despite no significant change in total PUFA levels. ROC analysis highlighted certain FAs with high AUC values, especially in HT and follicular cell adenoma, indicating potential as diagnostic biomarkers. MSEA revealed disruptions in pathways related to α-linolenic and linoleic acid metabolism and β-oxidation of very long-chain FAs. These findings suggest FA profiling could support the diagnosis of thyroid disorders and offer new insights into disease-related metabolic changes.